Free throw violation or not?

[Philz]

I know Badnews, but why wouldnt more players do that if its legal?....they could start out running say 20 feet before the 3 point line and time it so they break the plane just after or on the release and they would most likely get the rebound with the momentum they were able to gain before the shot.....I never see this on TV, mostly see it REC league and youth league game and alway see the Refs call it a violation and and as I stated nobody seems to question it but me and as you mentioned they just have to stay behind the line until the release which they do according to the rule but the momentum they get from getting a head start by running and timming the free throw I feel is a great advantage.